conf: introduce configuration management

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 38 insertions, 0 deletions

diff --git a/conf/storewatcher.go b/conf/storewatcher.go
new file mode 100644
index 00000000..4f9c2ef7
--- /dev/null
+++ b/conf/storewatcher.go
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2019 WireGuard LLC. All Rights Reserved.
+ */
+
+package conf
+
+import "reflect"
+
+type StoreCallback func()
+
+var storeCallbacks []StoreCallback
+
+func RegisterStoreChangeCallback(cb StoreCallback) {
+	startWatchingConfigDir()
+	cb()
+	storeCallbacks = append(storeCallbacks, cb)
+}
+
+func UnregisterStoreChangeCallback(cb StoreCallback) {
+	//TODO: this function is ridiculous, doing slow iteration like this and reflection too.
+
+	index := -1
+	for i, e := range storeCallbacks {
+		if reflect.ValueOf(e).Pointer() == reflect.ValueOf(cb).Pointer() {
+			index = i
+			break
+		}
+	}
+	if index == -1 {
+		return
+	}
+	newList := storeCallbacks[0:index]
+	if index < len(storeCallbacks)-1 {
+		newList = append(newList, storeCallbacks[index+1:]...)
+	}
+	storeCallbacks = newList
+}